It was a contentious showdown, but after many lead changes, Bad Meets Evil's "Lighters," featuring Bruno Mars, bested Britney Spears' "I Wanna Go" to take MTV News' Song of Summer crown.

Nearly a half-million votes were cast, though a vast majority (327,679) of those were split almost evenly between Royce Da 5'9" and Eminem's joint project and Spears. Fan groups rallied behind their respective favorites, leading to a lot of back-and-forth over the past few days, but "Lighters" ultimately came out ahead when polls closed earlier Wednesday (September 7), taking 38.2 percent of the tally with 167,202 votes. The track has turned into a summer sleeper hit for Em, Royce and Mars. It is currently holding strong at #4, its peak position so far, on the Billboard Hot 100, 11 weeks after debuting on the chart.

Spears' "I Wanna Go" — the third Billboard top 10 hit from Femme Fatale — trailed with just over 36.6 percent. If Spears is less than pleased with coming in second, she can take comfort in knowing that her 160,477 votes put her way ahead of her nearest competitor, Lady Gaga, by well over 100,000 votes.

Taking 11.91 percent of the poll, Gaga's "The Edge of Glory" came in third with 52,126 votes. The only other song to pull down a sizable number of votes was Rihanna's "S&M," a track released in late spring that topped the charts early this summer, which garnered 34,681 votes for 7.92 percent of the tally.

Interestingly, many of the summer's biggest chart hits found themselves without much love in our Newsroom poll. Among the songs that reached #1 on the Billboard singles chart but found themselves with fractional percentages of the vote here were Katy Perry's history-making "Last Friday Night (T.G.I.F.)" with just 1.26 percent, Adele's "Rolling in the Deep" (0.33 percent), LMFAO's "Party Rock Anthem" (0.71 percent) and this week's Hot 100 #1, Maroon 5 and Christina Aguilera's "Moves Like Jagger" (0.98 percent).

Radio hits from Pitbull and Nicki Minaj also missed the boat with 3,090 votes (0.71 percent) and 1,655 votes (0.38 percent), respectively, for "Give Me Everything" and "Super Bass," while "Dirty Dancer" by Enrique Iglesias featuring Usher and Lil Wayne took 0.28 percent and "Otis" from Throne duo Jay-Z and Kanye West scored just 0.12 percent (or 524 votes).

The numbers for mainstream artists like Perry, Minaj and West were fairly similar to those accrued by lower-profile acts Foster the People, Cobra Starship and David Guetta. Foster's "Pumped Up Kicks" earned the band 0.14 percent of our poll, with slightly bigger numbers falling to Cobra's "You Make Me Feel" (0.25) and Guetta's "Where Them Girls At" (0.16).